For Chinese and Japanese, they usually make use of word-group when typing (input two or more characters by press space-key once after type many letters). With JUCE TextEditor, it's normal on Windows, OSX and iOS, but it only accepts the first character on Android however you type how many letters. (TextEditor still doesn't accept any non-English character on Linux and I haven't found a easy way to figure out this knot.)

I did some search, see:

http://www.juce.com/forum/topic/japanese-input

Seems exactly the same problem. This time, eventually, it's Android's turn :)